Just ask the folks behind Candy Crush, Fallout Shelter, Miitomo, and Clash Royale. However it seems that while in-app purchases does sound like the path to financial success for apps, Google doesn’t really want developers to include the option when developing apps for their virtual reality platform, Daydream.
According to Google’s guidelines, they have suggested that in-app purchases inside VR games might not lead to the financial success that they are hoping for. The reason for this is simple: by including in-app purchases, it kind of “breaks” the fantasy/immersion that you are in a virtual world. Or imagine playing a game like Farmville where you have to rely on timers or in-app purchases to continue playing, you might as well be playing the game without virtual reality, right?
Of course this is entirely up to the developer at the end of the day since this is just a guide, but Google does have a point and hopefully this is one that we hope developers will pay heed to.